With the rapid development of multimedia technology, use of digital devices such as digital still cameras (“still cameras”) and digital video cameras (“video cameras”) has become wide-spread in many countries. Furthermore, more and more mobile phones and PDAs (personal digital assistants) are combined with digital lens units. Therefore, lens units are in great demand. Nowadays, lens units are still very expensive due to the high rejection during quality control.
Generally, when assembling lenses, lens pieces, spacers, aperture pieces and other elements are pressed into a barrel so as to form a lens unit. Then modulation transfer function (MTF) testing is applied to test clarity and contrast of the lens unit. Before pressing the lens pieces, spacers, aperture pieces and other elements into the barrel, pressing parameters such as pressure and pressing velocity are predetermined so as to obtain flawless lens units. However, if the pressing parameters are changed during assembly, many flawed lens units may be produced before the change in pressing parameters is discovered.
What is needed, therefore, is an assembling and testing device, which overcomes the above-described problems.